화학공학소재연구정보센터
Applied Surface Science, Vol.289, 6-13, 2014
Effect of water on hydrogenation of 1,3-butadiene over Au (111): A joint theoretical and experimental study
The effect of water on the hydrogenation of 1,3-butadiene over Au (1 1 1) was investigated based on density functional theory calculations and the results were compared with experimental study on the same reaction over Au/gamma-Al2O3 catalysts prepared by different methods. All possible adsorption sites and geometry structures of hydrogen, water and 1,3-butadiene on Au (1 1 1) were considered in the adsorption energy calculations to obtain the optimized adsorption modes. The hydrogenation of 1,3-butadiene was found to be only feasible with dissociated H atoms adsorbed over Au (1 1 1). Our adsorption calculations suggest that H2O tended to block the active sites and inhibited the adsorption step, fully consistent with the rapid 1,3-butadiene conversion drop from above 40% to below 10% at low water concentration (<1200 ppm) in experiments. The transition state calculations indicate that water had little impact on the reaction step given slight change of energy barrier from 0.62 eV to 0.55 eV for the major route. This result validated the experimental finding that the conversion of 1,3-butadiene on Au/gamma-Al2O3 catalysts had only a slight decrease in a high water concentration range. (C) 2013 Elsevier B.V. All rights reserved.